Commit d56dbf5b authored by Yinghai Lu's avatar Yinghai Lu Committed by Bjorn Helgaas
Browse files

PCI: Allocate 64-bit BARs above 4G when possible 

Try to allocate space for 64-bit BARs above 4G first, to preserve the space
below 4G for 32-bit BARs.  If there's no space above 4G available, fall
back to allocating anywhere.

[bhelgaas: reworked starting from http://lkml.kernel.org/r/1387485843-17403-2-git-send-email-yinghai@kernel.org

]
Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent f75b99d5

drivers/pci/bus.c

+13 −3
Original line number Diff line number Diff line
@@ -102,6 +102,8 @@ static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL}; 
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT

static struct pci_bus_region pci_64_bit = {0,

				(dma_addr_t) 0xffffffffffffffffULL};

static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,

				(dma_addr_t) 0xffffffffffffffffULL};

#endif



/*
@@ -198,8 +200,7 @@ static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res, 
 * alignment and type, try to find an acceptable resource allocation

 * for a specific device resource.

 */

int

pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,

int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,

		resource_size_t size, resource_size_t align,

		resource_size_t min, unsigned int type_mask,

		resource_size_t (*alignf)(void *,
@@ -209,10 +210,19 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, 
		void *alignf_data)

{

#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT

	if (res->flags & IORESOURCE_MEM_64)

	int rc;



	if (res->flags & IORESOURCE_MEM_64) {

		rc = pci_bus_alloc_from_region(bus, res, size, align, min,

					       type_mask, alignf, alignf_data,

					       &pci_high);

		if (rc == 0)

			return 0;



		return pci_bus_alloc_from_region(bus, res, size, align, min,

						 type_mask, alignf, alignf_data,

						 &pci_64_bit);

	}

#endif



	return pci_bus_alloc_from_region(bus, res, size, align, min,

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